private bool ReadInputFuel()
{
if (ValidateFuelInput())
{
var currReading = double.Parse(textBoxCurrOdoRead.Text);
var prevReading = double.Parse(textBoxPrevOdoRead.Text);
var fuelAmount = double.Parse(textBoxFuelInput.Text);
var unitPrice = double.Parse(textBoxLiterPriceInput.Text);
// check if positive number
if (currReading < 0 || prevReading < 0 || fuelAmount < 0 || unitPrice < 0)
{
errorMsg = "Make sure that all numerals are positive.";
return(false);
}
// check if currReading > prevReading
else if (currReading < prevReading)
{
errorMsg = "The current odometer reading must be larger than the previous odometer reading.";
return(false);
}
else
{
fuelCalculator = new FuelCalculator(currReading, fuelAmount, prevReading, unitPrice);
return(true);
}
}
return(false);
}